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61.
Ivan Mrkic Mohamed Abughren Jasna Nikolic Uros Andjelkovic Emilia Vassilopoulou Athanassios Sinaniotis Arnd Petersen Nikolaos G. Papadopoulos Marija Gavrovic-Jankulovic 《Molecular biotechnology》2014,56(6):498-506
Allergy to banana fruit appears to have become an important cause of fruit allergy in Europe. Among five allergens that have been found, beta-1,3-glucanase denoted as Mus a 5 was identified as a candidate allergen for the component-resolved allergy diagnosis of banana allergy. Because of the variations in protein levels in banana fruit, in this study Mus a 5 was produced as a fusion protein with glutathione-S-transferase in Escherichia coli. The recombinant Mus a 5 was purified under native conditions by a combination of affinity, ion-exchange, and reversed phase chromatography. N-terminal sequence was confirmed by Edman degradation and 55 % of the primary structure was identified by mass fingerprint, while the secondary structure was assessed by circular dichroism spectroscopy. IgG reactivity of recombinant protein was shown in 2-D immunoblot with anti-Mus a 5 antibodies, while IgG and IgE binding to natural Mus a 5 was inhibited with the recombinant Mus a 5 in immunoblot inhibition test. IgE reactivity of recombinant Mus a 5 was shown in ELISA within a group of ten persons sensitized to banana fruit. Recombinant Mus a 5 is a novel reagent suitable for the component-resolved allergy diagnosis of banana allergy. 相似文献
62.
Ramona Moles Sarkis Sarkis Veronica Galli Maria Omsland Maria Artesi Massimiliano Bissa Katherine McKinnon Sophia Brown Vincent Hahaut Robyn Washington-Parks Joshua Welsh David J. Venzon Anna Gutowska Melvin N. Doster Matthew W. Breed Kristin E. Killoran Joshua Kramer Jennifer Jones Marcin Moniuszko Anne Van den Broeke Cynthia A. Pise-Masison Genoveffa Franchini 《PLoS pathogens》2022,18(4)
We investigated the impact of monocytes, NK cells, and CD8+ T-cells in primary HTLV-1 infection by depleting cell subsets and exposing macaques to either HTLV-1 wild type (HTLV-1WT) or to the HTLV-1p12KO mutant unable to infect replete animals due to a single point mutation in orf-I that inhibits its expression. The orf-I encoded p8/p12 proteins counteract cytotoxic NK and CD8+ T-cells and favor viral DNA persistence in monocytes. Double NK and CD8+ T-cells or CD8 depletion alone accelerated seroconversion in all animals exposed to HTLV-1WT. In contrast, HTLV-1p12KO infectivity was fully restored only when NK cells were also depleted, demonstrating a critical role of NK cells in primary infection. Monocyte/macrophage depletion resulted in accelerated seroconversion in all animals exposed to HTLV-1WT, but antibody titers to the virus were low and not sustained. Seroconversion did not occur in most animals exposed to HTLV-1p12KO. In vitro experiments in human primary monocytes or THP-1 cells comparing HTLV-1WT and HTLV-1p12KO demonstrated that orf-I expression is associated with inhibition of inflammasome activation in primary cells, with increased CD47 “don’t-eat-me” signal surface expression in virus infected cells and decreased monocyte engulfment of infected cells. Collectively, our data demonstrate a critical role for innate NK cells in primary infection and suggest a dual role of monocytes in primary infection. On one hand, orf-I expression increases the chances of viral transmission by sparing infected cells from efferocytosis, and on the other may protect the engulfed infected cells by modulating inflammasome activation. These data also suggest that, once infection is established, the stoichiometry of orf-I expression may contribute to the chronic inflammation observed in HTLV-1 infection by modulating monocyte efferocytosis. 相似文献
63.
Athanassios Vassilopoulos Chu-Xia Deng Triantafyllos Chavakis 《The international journal of biochemistry & cell biology》2010,42(2):193-197
Neovascularisation is critical in several malignant and inflammatory conditions, as well as in the course of eye disorders. During new vessel formation, endothelial cell functions, such as proliferation and sprouting are very important and are regulated by a variety of growth factors. The DNA damage response machinery as well as factors regulating histone modifications, such as histone deacetylases, regulate cell fate as well as gene expression. Recent evidence has pointed to potential interactions among BRCA1, H2AX and SIRT1 in these intracellular pathways and neovascularisation, which will be reviewed here. 相似文献
64.
It is commonly accepted that introduced species have recruitment advantages over native species. However, this idea has not been widely tested, and those studies that have compared survival of introduced and native species have produced mixed results. We compiled data from the literature on survival through germination (seed to seedling survival), early seedling survival (survival through one week from seedling emergence) and survival to adulthood (survival from germination to first reproduction) under natural conditions for 285 native and 63 introduced species. Contrary to expectations, we found that introduced and native species do not significantly differ in survival through germination, early seedling survival, or survival from germination to first reproduction. These comparisons remained non-significant after accounting for seed mass, longevity and when including a random effect for site. Results remained consistent after excluding naturalized species from the introduced species data set, after performing phylogenetic independent contrasts, and after accounting for the effect of life form (woody/non-woody). Although introduced species sometimes do have advantages over native species (for example, through enemy release, or greater phenotypic plasticity), our findings suggest that the overall advantage conferred by these factors is either counterbalanced by advantages of native species (such as superior adaptation to local conditions) or is simply too small to be detected at a broad scale. 相似文献
65.
Allan F. Wiechmann Athanassios P. Kyritsis R. Theodore Fletcher Gerald J. Chader 《Journal of neurochemistry》1990,55(1):208-214
Abstract: Melatonin is synthesized by cultured Y79 human retinoblastoma cells and is secreted into the medium. Activity of the two key enzymes involved in the synthesis of melatonin, N -acetyltransferase (NAT) and hydroxyindole- O -methyl-transferase (HIOMT), are present in retinoblastoma cells. The activity of these enzymes and the resulting synthesis and release of melatonin are modulated by the addition of a cyclic AMP analogue and butyrate to the culture medium. Melatonin levels increase dramatically over control levels after the addition of dibutyryl cyclic AMP (dbcAMP), whereas melatonin levels decrease after butyrate treatment. HIOMT activity is inhibited by both dbcAMP and butyrate, and NAT activity is stimulated by both of these differentiating agents, suggesting that the rise in melatonin levels in response to dbcAMP is the result of increased activity of NAT, whereas the decline in melatonin levels in response to butyrate may be due to a drop in HIOMT activity. Melatonin synthesis is dose- and time-dependent, and the effect of dbcAMP is readily reversible, whereas the effect of butyrate does not appear to be reversible. These effects probably reflect basic differences in the regulatory mechanisms of the inducing agents. 相似文献
66.
Citizen science in schools: Engaging students in research on urban habitat for pollinators
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Manu E. Saunders Erin Roger William L. Geary Floret Meredith Dustin J. Welbourne Alex Bako Emily Canavan Francesca Herro Charlotte Herron Olivia Hung Madeline Kunstler Jade Lin Natasha Ludlow Mayling Paton Sunny Salt Tallulah Simpson Ariana Wang Nikki Zimmerman Kalani B. Drews Hayley F. Dawson Lachlan W. J. Martin Jack B. Sutton Chiquita C. Webber Amy L. Ritchie Leigham D. Berns Bella A. Winch Holly R. Reeves Eiron C. McLennan Jordan M. Gardner Charli G. Butler Emily I. Sutton Max M. Couttie Jake B. Hildebrand Isabella A. Blackney Justine A. Forsyth Deborah M. Keating Angela T. Moles 《Austral ecology》2018,43(6):635-642
Citizen science can play an important role in school science education. Citizen science is particularly relevant to addressing current societal environmental sustainability challenges, as it engages the students directly with environmental science and gives students an understanding of the scientific process. In addition, it allows students to observe local representations of global challenges. Here, we report a citizen science programme designed to engage school‐age children in real‐world scientific research. The programme used standardized methods deployed across multiple schools through scientist–school partnerships to engage students with an important conservation problem: habitat for pollinator insects in urban environments. Citizen science programmes such as the programme presented here can be used to enhance scientific literacy and skills. Provided key challenges to maintain data quality are met, this approach is a powerful way to contribute valuable citizen science data for understudied, but ecologically important study systems, particularly in urban environments across broad geographical areas. 相似文献
67.
Proferrorosamine A (pFR A) of the plant pathogenic bacterium Erwinia rhapontici was shown to inhibit growth of wheat and cress seedlings at the 10 ppm level. When the seeds were continuously exposed to 100 ppm pFR A, the germination of cress and wheat seeds was inhibited up to 90% and 80%, respectively. The inhibition could be reversed through addition of equimolar amounts of ferrous iron, which indicates that the strong iron chelating capability of pFR A is responsible for the observed effect. The Fe(II) in the corresponding iron complex, ferrorosamine A, was found to be remarkably resistant towards oxidation by hydrogen peroxide and therefore redox-cycling in the Haber-Weiss cycle. It is thus conceivable that pFR A may also attenuate the generation of reactive hydroxyl radicals during the resistant and wound reaction. The apparent correlation between proferrorosamine production and virulence in erwiniae was further corroborated through the analysis of Erwinia persicinus, a newly described species. Using electrospray ionization mass spectrometry, E. persicinus was shown to produce pFR A and pFR B, and preliminary evidence for the phytopathogenicity of E. persicinus was found in cress. Inhibition of wheat seedlings by E. persicinus could not be demonstrated, but this may be due to technical difficulties or different host specificities. Taken together, our results indicate that the phytopathogenicity of E. rhapontici and E. persicinus may, as least in part, be due to the release of proferrorosamines. 相似文献
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70.
Programmed cell death consists of two major types, apoptotic and autophagic, both of which are mainly defined by morphological criteria. Our findings indicate that both types of programmed cell death occur in the ovarian nurse cells during middle- and late-oogenesis of Drosophila virilis. During mid-oogenesis, the spontaneously degenerated egg chambers exhibit typical characteristics of apoptotic cell death. Their nurse cells contain condensed chromatin and fragmented DNA, whereas active caspase assays and immunostaining procedures demonstrate the presence of highly activated caspases. Distinct features of autophagic cell death are also observed during D. virilis mid-oogenesis, as shown by monodansylcadaverine staining and ultrastructural examination performed by transmission electron microscopy. Additionally, atretic egg chambers exhibit an accumulation of lysosomal proteases. At the late stages of D. virilis oogenesis, apoptosis and autophagy coexist, manifesting cell death features that are similar to the ones described above, being also escorted by the involvement of an altered cytochrome c conformational display. We propose that apoptosis and autophagy operate synergistically during D. virilis oogenesis for a more efficient elimination of the degenerated nurse cells. 相似文献